This paper is organised as follows: In §2, we measure \(j\)  of dark matter haloes in a
cosmological dark matter-only simulation. We investigate its dependence on the halo radius within which \(j\)  is measured
and the halo radius at which the rotation velocity is measured. The resulting predictions of dark matter halo \(j\)  are compared
to \(j\)  measured for a large observational sample of local galaxies for which the completeness is known in §3.
A discussion of the results is in §4. We adopt a \(\Lambda \) CDM concordance universe (\(\Omega _m=0.24, \Omega _{\Lambda }=0.76,h=H_0/[100\)  km s\(^{-1}\)  Mpc\(^{-1}] = 0.73, \sigma _8 = 0.77, n = 0.958),\)  i.e.,
within one standard deviation of both the WMAP 3 and 5 year best estimates [1]}, [2]}.
All logarithms are base ten.
